mpickering / core-kythe

There are two parts in this repo currently.

The first is a plugin which prints out core and emits kythe cross-links for it.

The second is a nix function which recursively indexes and creates tables for all the dependencies of a project.

Plugin Usage

Enter the environment with the plugin.

nix-shell

(This will take a while (1-2 hours) as it will build GHC).

To use the plugin.

ghc -fplugin KythePlugin -fplugin-opt KythePlugin:logs T.hs
./serve.sh logs/ localhost:8080

Then access localhost:8080 in order to view the cross linked source.

ghcWithIndexer

nix-shell haskell-with-indexer.nix
serve

Will build the conduit package by default and cross-link all its dependencies. There are some problems with the resulting directory structure but everything fundamentally works.

You can modify which package is built by changing ps.conduit in the nix file.

Examples

There are also some examples which can be rendered if kythe is installed.

./serve examples/ localhost:8080

Will render the output for 5 simple files from two projects.

core-kythe's Issues

Set the right flags for -ddump-simpl

Currently I don't try and set the right flags (ie -dsuppress-ticks -g -dsuppress-unfoldings) I should modify DynFlags rather than make the user set them.

More rigid document structure

Currently all the files are dumped into one folder. This is not very ergonomic.

Recursive blocks are not cross-linked

This is due to a simple oversight - there is a missing case in pprTopBind for the Rec case.

https://github.com/ghc/ghc/blob/wip/annotate-core/compiler/coreSyn/PprCore.hs#L107

Cross-module support

I need to work out a way of passing the tick information between modules. For now it will be easiest to serialise to files I think.

Decls don't work properly with -dsuppress-all

Turning on the flag -dsuppress-all causes cross-linking to break.

Type arguments are not cross referenced.

The binding sites are marked as definition sites but the use sites are not linked back to them.

This is because these types are printed by pprArg and then eventually by ppr_ty in IfaceType.

Definition site is on type signature, not on actual definition binded.

Join points are not linked

They have special handling in pprCore which I have left alone for now.

Type arguments are not linked properly

Permissions issue when serving

I'm following https://github.com/mpickering/core-kythe/blob/23e690883f1b56e830a49e07a8ea1785ee5a390e/README.md#ghcwithindexer

but when I run serve I get:

[nix-shell:~/src/haskell/core-kythe]$ serve
2017/08/29 16:13:15 Error opening db at "/nix/store/xm92l97915kgb83w49sb1wx9vq751g0z-haskell-indexer-local-0.1/share/tbl": could not open LevelDB at "/nix/store/xm92l97915kgb83w49sb1wx9vq751g0z-haskell-indexer-local-0.1/share/tbl": IO error: /nix/store/xm92l97915kgb83w49sb1wx9vq751g0z-haskell-indexer-local-0.1/share/tbl/LOCK: Permission denied

It seems to try to open a LevelDB lock file inside the nix store; that can't work because it's read-only.